Veron's set is great for wild corals, for captive stuff I guess I'd probably go with Aquarium Corals by Borneman.
There's nothing `sps-only' focused that I've seen, and the biologists tend to see stony corals as one, so I'm hoping for a `stony-only' care/ID book.
Until then, I guess:
<a href="http://www.amazon.com/exec/obidos/ASIN/1890087483/reeflink" target="_blank"><b>Aquarium Corals</b></a><br>Selection, Husbandry, and Natural History<br><i>by Eric Borneman</i><br><a href="http://www.amazon.com/exec/obidos/ASIN/1890087483/reeflink" target="_blank"><img src="http://images.amazon.com/images/P/1890087483.01.TZZZZZZZ.jpg"></a>